Printing-frame.



PATH-@TED JULY s, 1906. E. W. SWBIGARD., PRINTING FRAME.

APPLICATION FILED 0G'l.7. 1905.

Fifi MNHN lllllllllllill W my www UNITED sTATEs PATENT oEEioE.

EMANUEL w.v swEiGARD, 0E CHICAGO, ILLINOIS,

' PRINTING-fERAME.

Specification of Letters Patent.

Application led October 7l 1905. Serial No. 281.720,

Patented July 3, 106.

To all whom it may concern: v

Beit known that I, EMANUEL W. SwEI- GARD a citizen of the United Statesof America, residing at Chicago, in the county of Cook and State ofIllinois, have invented certain new and useful Improvements inPrinting-Frames, of which the following is a speci` plan of thebackboard thereof. Fig. 3 is a section in the line 3 3 of Fig. 2. Fig. 4is a section in the line 4 4 of Fig. 2, and Fig. 5 is a section in theline 5 5 of Fig. 4.

Referring to the drawings, A is a hollow rectangular frame o f thevordinary sort, such as 1s used in photo-en aving, the same being rovidedwith a thic glass plate B at its ont and at its back with a plurality ofhinged pressure-bars C, A having mechanism for clamping them down. Inmakingphotoengravin s and the like a photograph-negative oft e ordinarysort is first. made and after that a print on a metal plate, usually ofzinc.

that the metal plate andthe negative be brought into as close contact as1s accom-` plished in ordinary printing between the paper and thenegative. To eifect such a close contact requires a degree of pressurerequiring special appliances and backboards of exceptional strength. Myinvention resides 'in the backboard of the device, which I will the endsof the board thus formed and in the middle also, if the klboard islarge) 4are secured cleats E ,V theI said cleats being secured to theV*board by means of screws E', passed through perforations in the boardand throu 'h rubber sleeves `e in saidl perforaltions. he lower faces ofthe board are countersunk at e', so that the heads of the screws E willlie below the face of the board, so as not to interrupt its smoothsurface, and -said countersunk spaces e contain two erforated plates, anupper plate e2 and a' owerplate e?. The

' perforation in the lower plate iits the screw 5 In makingthis plate itis necessaryy but the perforation in the upper plate is somewhat larger,so as to admit of considerable lateral movement of the screw therein. Inuse these backboards receive all sorts of bad treatment, being fr'euently soaked and subjected to levery kind o warping influence. Thecleats being on the upper faces of the boards and being more exposed tothe air are usually drier than the main portions of the boards, and as aresult the cleats cause rather than revent warping. With myconstruction, iiowever, when the boards are wet and swell and the cleatsdo not elongate the boards can slide on the cleats, theconnectingscrewsE/ moving laterally in the perforations provided for the urpose andcompressing the small rubber s eeves which surround them. Simultaneouslythe two metal plates e3 e3 can slide on each other, so that the boardsare permitted to elongate independ-- ently of the cleats. The4 cleatsare, however,virmly clamped to the boards, so as to prevent warpingthereof.

It is necessary to inter ose some kind of an elastic spring between t epresser-bars and the backboards of these frames, and it has vbeenexceedingly diflioult to find a suitablev elastic substance. If a solidblock of coml plaratively hard rubber be used, it is not sufcientlyelastic, while if softer rubber be used it is not sufficiently durable.As an elastic medium in my device I provide a plurality of rubbercylinders F, each of which is provided with a number of verticalperforations and a single central perforation f', whic its tightly 4overthe head of a screw f 2, holding the cylinder in place. Depressions areformed below the cylinders in the face of the board, which depressionsare adapted to revceive'the lower ends of 'the cylinders when pressureis applied thereto. I ind that these cylinders are extremely elastic andexceedingly durable.

I claim as new and desire to secure by Letters Patent- 1 IOO 1. Inprinting-frames, a backboard com- IIO 3. In printing-frames, abackboard, cleats on the backboard, and screws assed through thebackboard and securing tv e cleats thereto, the

4. In printing-frames, a backboard, cleats on the backboard, screwspassed through the backboard and securing the cleats thereto,

the perforations for said screws being of ves lar er dfameter than thescrews themselves,

Yan rubber sleeves surrounding the screws.

6. In printing-frames, a backboard countersunk on its'lower surface andperforated erforations for said screws being ofl Y. larger dlameter thanthe screws themselves.

coaxally with the countersunl spaces, rub- 26 ber sleeves in theerforations, two washers in the countersunl spaces, one of' which ismovable, and screws passed through the washers, and a cleat which thescrews enter. 7. In printing-frames, a backboard, having depressions onits faces, a clamp, and transversely-perforated rubber blocks of largerdiameter than the de ressions arranged between the backboar and clampand above the depressions.

In witness whereof I have signed the above a plication for LettersPatent, at Chicago, in the county of Cook and State of Illinois, this4th day of October, A. D. 1905` Y EIMAIWJIEII SWEIGARD Witnesses:

CHAs. O. SHERVEY. K.4 M. CORNWALL.

